Let me give you some information on the RAZR chargers etal.
The RAZR charger works fine on the BlackBerry but I would not recommend more than 4 continuous hours using that charger (SPN5202) on your BB. The Normal BB charger is 500mAh, The RAZR rapid is 850mAh. This difference over time will shorten the life of the battery. Heat is a by-product of charging... heat kills batteries.
The BB External charger is 750mAh but provides a switching output when the battery reaches 85% the output cuts in half. The HTC chargers are typically 1000mAh (2x the normal BB charger).
If you want an OEM charger for your BB may I suggest the new "Blade" style http://smartphonedepot.com/shop/prod...cat=282&page=1